The Material. Custom rigid boxes come in a wide variety of materials, but most commonly, these boxes contain some variation of cardboard, fiberboard, or plywood. The Cost. Custom rigid boxes can be expensive to produce, which explains why they aren't the primary material for standard packaging boxes. They're more costly than standard folding cartons, yes, but they are also more costly to print (unless you print on disc).
Printing. On the face of it, printing on rigid boxes might seem like an expensive proposition. After all, what are the chances that you'll be able to get a specialized, attention-grabbing color on this large box? Well, it depends. Many printing companies today offer a variety of options when it comes to the standard printing packages - they don't just offer standard black and white (or even sepia or grey!)
There are now, however, several ways to make printing on custom rigid boxes more cost-effective. Most of these "razor-thin" options are geared toward high-end industrial printing with glossy or metallic finishes. This is ideal for packaging, but not ideal for more low-cost or basic packing materials. For example, there are several different styles of luxury rigid boxes that are only available in silver, gold (or other similar colors), or other more luxurious colors.